The night sky was clear and the moon was about a quarter full, so you could see the stars. At first, I did not notice it until my dog started barking towards Black Mesa. I tried to tell get him to stop barking, but he would not. So I looked towards where he was barking and he was barking at a light that was top of Black Mesa. It seemed like it was nothing and then all the dogs in the area starting barking too. So I kept watching the light along with the dogs. Then my dad came out of the house to see why the dogs were barking. So I told him they where barking at the light over Black Mesa. It was shaped like a oval, light. The color of the light was white in the center, and around it was two other colors yellow and lite blue. The colors seemed to virbate bright and then dimed back and forth. It was floating on top of Black Mesa very slowly for about 15 to 20 minutes. It started from the east side of the mesa, going west. I did not see were it went, but it was gone. Then I just went back inside with my dad.